package easy;

/**
 * 合并二叉树
 */
public class mergeTrees {

    class TreeNode {
        int val;
        TreeNode left;
        TreeNode right;

        TreeNode() {
        }

        TreeNode(int val) {
            this.val = val;
        }

        TreeNode(int val, TreeNode left, TreeNode right) {
            this.val = val;
            this.left = left;
            this.right = right;
        }
    }

    public TreeNode myCode(TreeNode root1, TreeNode root2) {

        if (root1 == null) {
            return root2;
        }

        if (root2 == null) {
            return root1;
        }

        TreeNode mergeNode = new TreeNode(root1.val + root2.val);
        mergeNode.left = myCode(root1.left, root2.left);
        mergeNode.right = myCode(root1.right, root2.right);
        return mergeNode;
    }
}
